Micofibrillar Cell Wall Extensions in the Hyphal Sheath of 'Postia placenta'

摘要

Evidence is provided for the existence of linear extracellular fibrillar elementsin the brown-rot fungus Postia placenta. These elements appear as structural components of the hyphal sheath and more closely resemble mycofibrils than fungal fimbriae. Mycofibrils are associated with and appear to originate from the hyphal surface when hyphae are grown on wood or inert substrates, such as glass cover slips and polycarbonate filters. These extracellular structures have a nominal diameter of 10-50 nm and are up to 25 micrometers in length. We conclude that mycofibrils are linear structural extensions of the hyphal cell wall. The precise function of mycofibrils in the brown-rot decay process of wood remains to be elucidated.